In high rise building elevator systems, the cab frame and the counterweight are interconnected by compensation ropes which descend in a loop down into the hoistway pit from the cab and counterweight. The compensation ropes balance the system to offset the weight of the traction cables in the elevator system. The compensation ropes do not support the weight of either the counterweight or cab assembly, as do the traction ropes, but merely provide an offsetting downward force on the cab or counterweight which balances the upward force imposed thereon by the weight of the traction cables.
At the present time, the compensation ropes are hitched to the cab frame by means of thimble rods and babbitted rope sockets; which, once installed, can only be adjusted within a limited range. This type of connection is perfectly acceptable from a strength standpoint, but is undesirable due to the relatively fixed nature of the connection. During extended operation of the elevator system, the traction ropes, and the compensation ropes (to a much smaller degree) will stretch, whereby the tensioning compensation sheave may be bottomed after a period of operation thereby resulting in a loss of tension and guidance on the compensation ropes. The normal load on each compensation rope is small (about 100 lbs.) and they stretch to a limited extent while the load on each hoist rope is rather large (about 1,500 lbs.) and there is considerable stretch. The only way to correct this problem is to adjust the length of the compensation ropes, which must be done relatively frequently. As noted previously, the babbitted rope sockets can only undergo limited adjustment, and in fact must be refitted and rebabbitted from time to time. This is time consuming, laborious and undesirable.